System and method for monitoring congestion paging

ABSTRACT

Systems and methods for monitoring a paging signal from a mobile switch to a cellular transmitter for occurrences of congestion. The system includes a switch; a cell site in communication with the switch, for broadcasting a page received from the switch to a cellular device configured to receive the page; and a monitoring module in communication with the switch for monitoring occurrences of paging congestion between the switch and the cell site.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates generally to mobile communications and,more particularly, to a system and method for monitoring paging signalstransmitted from a mobile switch to a cell site for occurrences ofcongestion.

2. Description of the Background

As mobile telephones have grown from mere voice communications devicesto sophisticated appliances for paging, text functions and Internetaccess, bandwidth management has become a critical function forproviding Quality of Service (QoS). A wireless communications networktypically includes a mobile switch, a paging area, and a cellular devicesuch as a cellular telephone. The mobile switch manages traffic betweencellular users. The paging area includes a plurality of cellulartelephone transmitters, or cell sites, that cover a certain geographicalarea. In operation, the mobile switch directs a page, addressed to acertain cellular device, to the appropriate paging area. A cell site,within the paging area, then broadcasts the page, causing, for example,a cellular phone to ring. In practice, network congestion occurs betweenthe mobile switch and a cell site, due in part to limited bandwidthbetween the switch and the cell site. Such congestion may cause pagessent from the switch to a targeted cellular device, via the cell site,to be lost. Lost pages cause users of cellular devices, such as cellularphones, to miss calls because the phone fails to ring. Pagingcongestion, therefore, significantly affects QoS. Additionally, pagingcongestion can lead to substantial revenue losses for telecommunicationsservice providers that fail to collect for unconnected calls.

A mobile switch may communicate with a cell site over a T-1 line. A T-1line is a commonly used digital line that bundles 24 channels calledDS0s, where each DS0 is capable of transmitting 64 kbps, for an overalltransmission rate of 1.5 Mbps. Some wireless communication networks,however, may limit paging communications to just one of the 24 channelsin a T-1 line, reserving the other 23 channels for transmitting voicedata. The growing popularity of cellular phones has caused the DS0channel dedicated to paging to operate at or beyond its 64 kbpscapacity. New services, such as short messaging service and messagewaiting indicators on cellular phones, also share the same DS0.

A network diagnostic tool is needed that enables service providers toidentify, and even quantify, instances of paging congestion. Such asystem needs to provide sufficient flexibility to identify pagingcongestion problems that exceed certain quantitative thresholds. Such asystem also needs to provide a notification system in which certainnetwork operators receive timely alerts when a paging congestion problemoccurs. The present invention satisfies this need.

SUMMARY OF THE INVENTION

The present invention is directed to systems and methods for monitoringa paging signal from a mobile switch to a cellular transmitter foroccurrences of congestion. According to one embodiment, the systemcomprises a switch; a cell site in communication with the switch, forbroadcasting a page received from the switch to a cellular deviceconfigured to receive the page; and a monitoring module in communicationwith the switch for monitoring occurrences of paging congestion betweenthe switch and the cell site.

The present invention may be used, for example, to monitor pagestransmitted from the mobile switch but not received by the cell site. Inthe case of a cellular phone, pages transmitted from the mobile switchcause the receiving cellular phone to ring. Lost pages, however, causecustomers to miss calls. The present invention may be used, for example,as a statistical tool for identifying operational problems that mightotherwise go unnoticed. In addition to statistical benefits, the presentinvention may also be used to notify network operators of pagingcongestions problems. Finally, the present invention may also be used asa loss of revenue indicator by quantifying the number of lost pages thatresulted in, for example, unconnected calls.

These and other benefits of the present invention will be apparent fromthe detailed description below.

DESCRIPTION OF THE FIGURES

For the present invention to be understood clearly and readilypracticed, the present invention will be described in conjunction withthe following FIGURE, wherein:

FIG. 1 is a block diagram of a cellular communications system accordingto one embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

It is to be understood that the figures and descriptions of the presentinvention have been simplified to illustrate elements that are relevantfor a clear understanding of the present invention while eliminating,for purposes of clarity, other elements. For example, certain systemdetails and modules of certain intelligent platforms are not describedherein. Those of ordinary skill in the art will recognize, however, thatthese and other elements may be desirable in a typical network. Adiscussion of such elements is not provided because such elements arewell known in the art and because they do not facilitate a betterunderstanding of the present invention.

FIG. 1 is a block diagram of a cellular communications system 10according to one embodiment of the present invention for monitoringpaging congestion between a mobile switch and a cell site. The system 10includes a page-monitoring module 12, a mobile switch 14, a publicswitched telephone network (PSTN) 16, a cell site 18, and a cellulardevice 20. The monitoring module 12, as described further hereinbelow,receives reports of missed pages from the mobile switch 14 and outputs anotification 22 to network operators 24, such as by email or page, whenthe number of missed pages due to paging congestion exceeds apredetermined amount. The mobile switch 14 is the bridge between thePSTN 16 and the cell site 18 that ultimately makes the wirelessconnection to the user's cellular device 20.

The monitoring module 12, which communicates with the paging queue ofmobile switch 14, may be implemented on an intelligent platform such as,for example, a computer, such as a workstation or a personal computer, amicroprocessor, a network server, or an application specific integratedcircuit, using any suitable type of computer instruction. Module 12 mayalso be implemented as software code to be executed by the system 10using any suitable computer language such as, for example, microcode,and may be stored in, for example, an electrically erasable programmableread only memory (EEPROM), or can be configured into the logic of thesystem 10. According to another embodiment, module 12 may be implementedas software code to be executed by the system 10 using any suitablecomputer language such as, for example, Java, Perl, C or C++ using, forexample, conventional or object-oriented techniques. The software codemay be stored as a series of instructions or commands on a computerreadable medium, such as random access memory (RAM), read only memory(ROM), a magnetic medium such as a hard-drive or a floppy disk, or anoptical medium such as CD-ROM. According to one embodiment, module 12may be integrated with the hardware or software of the mobile switch 14.

According to one embodiment, the switch 14 may be in communication withthe module 12, the PSTN 16, and the cell site 18 via a communicationsnetwork 25 including, individually or in combination, a wireline networkor wireless network. The communications network may include, forexample, individually or in combination, a plain old telephone system(POTS), a public switched telephone network (PSTN), a wireless telephonenetwork, the Internet, an intranet, a LAN, or a WAN, using, for example,packet-switching or circuit switching transmission modes. According toanother embodiment, the mobile switch 14 may be part of a mobileswitching center (MSC) in communication with the module 12 and the cellsite 18.

According to one embodiment, the monitoring module 12 is configured tocount the number of occurrences of paging congestion between the mobileswitch 14 and the cell site 18. An occurrence of paging congestionrefers to an instance where, for example, a cellular phone customer didnot receive notification of an incoming call. For example, when themobile switch 14 receives an incoming call directed to the cellulardevice 20, the mobile switch 14 issues a page 26 to the cellular device20 via the cell site 18. Normally, when the cellular device 20 receivesthe page 26, the cellular device 20 rings, notifying the cellularsubscriber of an incoming call. During instances of paging congestionbetween the mobile switch 14 and the cell site 18, however, the page 26may be lost. According to such an embodiment, module 12 may count thelost pages over a predetermined time interval.

According to another embodiment, module 12 may use the lost pageinformation to perform some corrective action. For example, module 12may notify network operators 24 when the number of lost pages reaches apredetermined limit, such as 100 lost pages in one hour. According tosuch an embodiment, module 12 may issue notification 22 to the networkoperators 24, such as by electronic mail or by page, via, for example, awide area network (WAN) 28. The notification 22 may include, forexample, the number of pages lost over some time interval. Notificationsmay also include information to facilitate troubleshooting, such as thelocation of paging congestion. The location may be designated by, forexample, paging area.

It should be understood that the invention is not limited by theforegoing description of preferred embodiments, but embraces all suchalterations, modifications, and variations in accordance with the spiritand scope of the appended claims.

1. An apparatus for monitoring paging congestion, comprising: a firstinterface to a mobile switch that transmits paging messages to becommunicated through a cell site from a public switched telephonenetwork in communication with the mobile switch, the mobile switchproviding a bridge between a public switched telephone network and thecell site; and a monitoring module in communication with a paging queueof the mobile switch via a second interface, the monitoring moduledetermining congestion in the transmission of the paging messagesbetween the mobile switch and the cell site by counting a number ofpaging messages that the mobile switch is unable to transmit to the cellsite via the first interface.
 2. The apparatus of claim 1, wherein thepaging message is adapted to alert the cell phone to ring for anincoming call.
 3. The apparatus of claim 2, wherein the incoming call isa voice communication.
 4. The apparatus of claim 1, wherein theapparatus communicates a notification responsive to the number ofmessages that the mobile switch is unable to transmit to the cell sitewithin a predetermined limit.
 5. The apparatus of claim 4, wherein thepredetermined limit is evaluated per a unit of time.
 6. The apparatus ofclaim 4, wherein the notification is at least one of an electronic mailmessage and a page.
 7. A computer-readable medium comprisingcomputer-readable instructions which, when executed on a computer, willcause the computer to: receive data from a paging queue of a bridgingdevice over a second interface concerning messages to be communicated toa cell site over a first interface from the bridging device which is incommunication between the cell site and a public switched telephonenetwork, the messages comprising information that is broadcast by thecell site to page a cell phone; and determine congestion in thetransmission of the paging messages between the cell site and thebridging device by counting a number of paging messages that a cell siteis unable to receive via the first interface of the bridging device. 8.The computer-readable medium of claim 7, wherein a paging message is apage adapted to alert the cell phone to ring for an incoming call. 9.The computer-readable medium of claim 8, wherein the incoming call is avoice communication.
 10. The computer-readable medium of claim 7,further comprising communicating a notification responsive to the numberof paging messages that the bridging device is unable to transmit to thecell site within a predetermined limit.
 11. The computer-readable mediumof claim 10, wherein the predetermined limit is evaluated per a unit oftime.
 12. The computer-readable medium claim 10, wherein communicatingthe notification comprises communicating at least one of an electronicmail message and a page.
 13. The apparatus of claim 1, wherein themonitoring module is located outside of the cell site.